username = "shenjialong"
password = "Anfang@123"

fail_times = 0
while True:
    if fail_times < 3:
        user = input("Input your username: ")
        pw = input("Input your password: ")
        if username == user and password == pw:
            print("{} login sucessfully !!!".format(user))
            fail_times = 0
            break
        else:
            print("The {} does not exist, or password error !!!".format(user))
            fail_times += 1
    else:
        print("Enter more than 3 times, Program exits ! ! !")
        break
# 一般返回密码或者账户的错误的信息